Such devices as the power window motors, switches, speakers or the like are incorporated into the sliding door used for a one box car or a wagon car or the like. In order to supply power to the devices from the vehicle body side, it must be designed that electric wire (wire harness) is arranged to run from the vehicle body side to the sliding door side, while the wire harness smoothly follow the opening and closing of the sliding door. A round wire having high flexibility has been conventionally used as the wire harness.
It is known that there is proposed the power supply apparatus for sliding door in which the wire harness winding unit is provided in the vehicle body side, and the surplus length of the wire harness accompanied with the opening and closing of the sliding door is wound so as to be adjusted (refer to Patent document 1).
It is also known that there is proposed the power supply apparatus for sliding door in which the corrugated tube receiving therein the wire harness is arranged to run with extra-length enough for bending between the prescribed position in the vehicle body and the sliding door, where one end of the corrugated tube is fixed to the sliding door, and the vicinity of the other end is supported in laterally movable by the bracket attached to the vehicle body (refer to Patent document 2).
Patent document 1: Japanese Patent Application Publication Hei 11-93514
Patent document 2: Japanese Patent Application Publication